Hello Guest!
Welcome to the official Square Foot Gardening Forum.
There's lots to learn here by reading as a guest. However, if you become a member (it's free, ad free and spam-free) you'll have access to our large vermiculite databases, our seed exchange spreadsheets, Mel's Mix calculator, and many more members' pictures in the Gallery. Enjoy.

Unless you're growing a true vining type of zuke like black forest it will most definitely NOT stay inside the 1 square foot. Check the book, "ALL NEW SQUARE FOOT GARDENING". I'm sure Mel recommends 9 SQUARES! (yep, 3 x 3) for zukes (zucchini). Mine took up more space than I had allotted last year so this year I'm giving them 9 squares. Yes, it's a lot of space, but they are big bushy suckers!

@RNmom7 wrote:Will I get into trouble if I plant zucchini. Will it be difficult to control? Does it stay inside the 1 foot? Or how much space should i allow?

RNMom:

I planted one zuke in each corner of the 4x8 and one in the center. They took over the whole bed. So yes zukes take up a lot of room in a SFG. One way to lessen the impact is to plant at the edge of the box and allow the zuke to take up part of the space between boxes or onto the walkway/lawn.

Lasts year in my "regular" garden, I planted 3 zucchini and one patty pan. I had them in a garden section that was 4 feet wide by 5 feet long.

I tried to train them up but had lots of problems with it. First the stems were not very strong and the plants were heavy. The result was that the plants tended to pull down from the tie off and buckle. I used a few poles to tie up so that might have also been part of the problem. The other issues I had were the large 1 foot leaves shaded the lower part of the plant and that part started to die out (leaved dropped, they stopped producing). After fighting them for a couple months, I pulled out the stakes and let them topple over. They were almost 3 feet tall at that point.

Once they were allowed to sprawl, the filled the space. I put up stakes to hold them in the bed. The plants themselves seemed happier. They started to branch out along the stem and produced more squash along these sections.

I would be willing to try vertical again in my SFG but would need more help on how to make it successful before I would try that again.